1

/*

     2

 *  matiec - a compiler for the programming languages defined in IEC 61131-3

     3

 *

     4

 *  Copyright (C) 2009-2011  Mario de Sousa (msousa@fe.up.pt)

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 *  Copyright (C) 20011-2012 Manuele Conti (manuele.conti@sirius-es.it)

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 *  Copyright (C) 20011-2012 Matteo Facchinetti (matteo.facchinetti@sirius-es.it)

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 *

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 *  This program is free software: you can redistribute it and/or modify

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 *  it under the terms of the GNU General Public License as published by

    10

 *  the Free Software Foundation, either version 3 of the License, or

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 *  (at your option) any later version.

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 *

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 *  This program is distributed in the hope that it will be useful,

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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

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 *  GNU General Public License for more details.

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 *

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 *  You should have received a copy of the GNU General Public License

    19

 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.

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 *

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 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

    24

 */

    25

    26

/*

    27

 * An IEC 61131-3 compiler.

    28

 *

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 * Based on the

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 * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

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 *

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 */

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    34

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/*

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 *  Fill candidate list of data types for all symbols

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 */

    38

    39

#include "print_datatypes_error.hh"

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#include "datatype_functions.hh"

    41

    42

#include <typeinfo>

    43

#include <list>

    44

#include <string>

    45

#include <string.h>

    46

#include <strings.h>

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#define FIRST_(symbol1, symbol2) (((symbol1)->first_order < (symbol2)->first_order)   ? (symbol1) : (symbol2))

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#define  LAST_(symbol1, symbol2) (((symbol1)->last_order  > (symbol2)->last_order)    ? (symbol1) : (symbol2))

    55

    56

#define STAGE3_ERROR(error_level, symbol1, symbol2, ...) {                                                                  \

    57

  if (current_display_error_level >= error_level) {                                                                         \

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    fprintf(stderr, "%s:%d-%d..%d-%d: error : ",                                                                            \

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            FIRST_(symbol1,symbol2)->first_file, FIRST_(symbol1,symbol2)->first_line, FIRST_(symbol1,symbol2)->first_column,\

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                                                 LAST_(symbol1,symbol2) ->last_line,  LAST_(symbol1,symbol2) ->last_column);\

    61

    fprintf(stderr, __VA_ARGS__);                                                                                           \

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    fprintf(stderr, "\n");                                                                                                  \

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    il_error = true;                                                                                                        \

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    error_found = true;                                                                                                     \

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  }                                                                                                                         \

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}  

    67

    68

    69

/* set to 1 to see debug info during execution */

    70

static int debug = 0;

    71

    72

print_datatypes_error_c::print_datatypes_error_c(symbol_c *ignore) {

    73

	error_found = false;

    74

	current_display_error_level = error_level_default;

    75

}

    76

    77

print_datatypes_error_c::~print_datatypes_error_c(void) {

    78

}

    79

    80

int print_datatypes_error_c::get_error_found() {

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	return error_found;

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}

    83

    84

/* a helper function... */

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symbol_c *print_datatypes_error_c::base_type(symbol_c *symbol) {

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	/* NOTE: symbol == NULL is valid. It will occur when, for e.g., an undefined/undeclared symbolic_variable is used

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	 *       in the code.

    88

	 */

    89

	if (symbol == NULL) return NULL;

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	return (symbol_c *)symbol->accept(search_base_type);

    91

}

    92

    93

    94

    95

    96

/*

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typedef struct {

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  symbol_c *function_name,

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  symbol_c *nonformal_operand_list,

   100

  symbol_c *   formal_operand_list,

   101

   102

  std::vector <symbol_c *> &candidate_functions,  

   103

  symbol_c &*called_function_declaration,

   104

  int      &extensible_param_count

   105

} generic_function_call_t;

   106

*/

   107

void print_datatypes_error_c::handle_function_invocation(symbol_c *fcall, generic_function_call_t fcall_data) {

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	symbol_c *param_value, *param_name;

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	function_call_param_iterator_c fcp_iterator(fcall);

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	bool function_invocation_error = false;

   111

	const char *POU_str = NULL;

   112

   113

	if (generic_function_call_t::POU_FB       == fcall_data.POU_type)  POU_str = "FB";

   114

	if (generic_function_call_t::POU_function == fcall_data.POU_type)  POU_str = "function";

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	if (NULL == POU_str) ERROR;

   116

   117

	if ((NULL != fcall_data.formal_operand_list) && (NULL != fcall_data.nonformal_operand_list)) 

   118

		ERROR;

   119

   120

	symbol_c *f_decl = fcall_data.called_function_declaration;

   121

	if ((NULL == f_decl) && (generic_function_call_t::POU_FB ==fcall_data.POU_type)) {

   122

		/* Due to the way the syntax analysis is buit (i.e. stage 2), this should never occur. */

   123

		/* I.e., a FB invocation using an undefined FB variable is not possible in the current implementation of stage 2. */

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		ERROR;

   125

	}

   126

	if (NULL == f_decl) {

   127

		/* we now try to find any function declaration with the same name, just so we can provide some relevant error messages */

   128

		function_symtable_t::iterator lower = function_symtable.lower_bound(fcall_data.function_name);

   129

		if (lower == function_symtable.end()) ERROR;

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		f_decl = function_symtable.get_value(lower);

   131

	}

   132

   133

	if (NULL != fcall_data.formal_operand_list) {

   134

		fcall_data.formal_operand_list->accept(*this);

   135

		if (NULL != f_decl) {

   136

			function_param_iterator_c fp_iterator(f_decl);

   137

			while ((param_name = fcp_iterator.next_f()) != NULL) {

   138

				param_value = fcp_iterator.get_current_value();

   139

   140

				/* Check if there are duplicate parameter values */

   141

				if(fcp_iterator.search_f(param_name) != param_value) {

   142

					function_invocation_error = true;

   143

					STAGE3_ERROR(0, param_name, param_name, "Duplicate parameter '%s' when invoking %s '%s'", ((identifier_c *)param_name)->value, POU_str, ((identifier_c *)fcall_data.function_name)->value);

   144

					continue; /* jump to next parameter */

   145

				}

   146

   147

				/* Find the corresponding parameter in function declaration */

   148

				if (NULL == fp_iterator.search(param_name)) {

   149

					function_invocation_error = true;

   150

					STAGE3_ERROR(0, param_name, param_name, "Invalid parameter '%s' when invoking %s '%s'", ((identifier_c *)param_name)->value, POU_str, ((identifier_c *)fcall_data.function_name)->value);

   151

					continue; /* jump to next parameter */

   152

				} 

   153

   154

				/* check whether direction (IN, OUT, IN_OUT) and assignment types (:= , =>) are compatible !!! */

   155

				/* Obtaining the assignment direction:  := (assign_in) or => (assign_out) */

   156

				function_call_param_iterator_c::assign_direction_t call_param_dir = fcp_iterator.get_assign_direction();

   157

				/* Get the parameter direction: IN, OUT, IN_OUT */

   158

				function_param_iterator_c::param_direction_t param_dir = fp_iterator.param_direction();

   159

				if          (function_call_param_iterator_c::assign_in  == call_param_dir) {

   160

					if ((function_param_iterator_c::direction_in    != param_dir) &&

   161

					    (function_param_iterator_c::direction_inout != param_dir)) {

   162

						function_invocation_error = true;

   163

						STAGE3_ERROR(0, param_name, param_name, "Invalid assignment syntax ':=' used for parameter '%s', when invoking %s '%s'", ((identifier_c *)param_name)->value, POU_str, ((identifier_c *)fcall_data.function_name)->value);

   164

						continue; /* jump to next parameter */

   165

					}

   166

				} else if   (function_call_param_iterator_c::assign_out == call_param_dir) {

   167

					if ((function_param_iterator_c::direction_out   != param_dir)) {

   168

						function_invocation_error = true;

   169

						STAGE3_ERROR(0, param_name, param_name, "Invalid assignment syntax '=>' used for parameter '%s', when invoking %s '%s'", ((identifier_c *)param_name)->value, POU_str, ((identifier_c *)fcall_data.function_name)->value);

   170

						continue; /* jump to next parameter */

   171

					}

   172

				} else ERROR;

   173

   174

				if (NULL == param_value->datatype) {

   175

					function_invocation_error = true;

   176

					STAGE3_ERROR(0, param_value, param_value, "Data type incompatibility between parameter '%s' and value being passed, when invoking %s '%s'", ((identifier_c *)param_name)->value, POU_str, ((identifier_c *)fcall_data.function_name)->value);

   177

					continue; /* jump to next parameter */

   178

				}

   179

			}

   180

		}

   181

	}

   182

	if (NULL != fcall_data.nonformal_operand_list) {

   183

		fcall_data.nonformal_operand_list->accept(*this);

   184

		if (f_decl)

   185

			for (int i = 1; (param_value = fcp_iterator.next_nf()) != NULL; i++) {

   186

				if (NULL == param_value->datatype) {

   187

					function_invocation_error = true;

   188

					STAGE3_ERROR(0, param_value, param_value, "Data type incompatibility for value passed in position %d when invoking %s '%s'", i, POU_str, ((identifier_c *)fcall_data.function_name)->value);

   189

				}

   190

			}

   191

	}

   192

   193

	if (NULL == fcall_data.called_function_declaration) {

   194

		function_invocation_error = true;

   195

		STAGE3_ERROR(0, fcall, fcall, "Unable to resolve which overloaded %s '%s' is being invoked.", POU_str, ((identifier_c *)fcall_data.function_name)->value);

   196

	}

   197

   198

	if (function_invocation_error) {

   199

		/* No compatible function exists */

   200

		STAGE3_ERROR(2, fcall, fcall, "Invalid parameters when invoking %s '%s'", POU_str, ((identifier_c *)fcall_data.function_name)->value);

   201

	} 

   202

   203

	return;

   204

}

   205

   206

void print_datatypes_error_c::handle_implicit_il_fb_invocation(symbol_c *il_operator, const char *param_name, symbol_c *called_fb_declaration) {

   207

	if (NULL == il_operand) {

   208

		STAGE3_ERROR(0, il_operator, il_operator, "Missing operand for FB call operator '%s'.", param_name);

   209

		return;

   210

	}

   211

	if (NULL == called_fb_declaration) {

   212

		STAGE3_ERROR(0, il_operand, il_operand, "Operand of FB call operator '%s' is not a FB variable.", param_name);

   213

		return;

   214

	}

   215

	if (NULL == prev_il_instruction) {

   216

		STAGE3_ERROR(0, il_operator, il_operand, "FB invocation operator '%s' must be preceded by a 'LD' (or equivalent) operator.", param_name);	

   217

		return;

   218

	}

   219

	/* Find the corresponding parameter in function declaration */

   220

	function_param_iterator_c fp_iterator(called_fb_declaration);

   221

	if (NULL == fp_iterator.search(param_name)) {

   222

/* TODO: must also check whther it is an IN parameter!! */

   223

		STAGE3_ERROR(0, il_operator, il_operand, "FB called by '%s' operator does not have a parameter named '%s'", param_name, param_name);	

   224

		return;

   225

	}

   226

	if (NULL == prev_il_instruction->datatype) {

   227

		STAGE3_ERROR(0, il_operator, il_operand, "Data type incompatibility between parameter '%s' and value being passed, when invoking FB.", param_name);

   228

		return;

   229

	}

   230

   231

	return;

   232

}

   233

   234

   235

/*********************/

   236

/* B 1.2 - Constants */

   237

/*********************/

   238

/******************************/

   239

/* B 1.2.1 - Numeric Literals */

   240

/******************************/

   241

void *print_datatypes_error_c::visit(real_c *symbol) {

   242

	if (symbol->candidate_datatypes.size() == 0) {

   243

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_REAL data type.");

   244

	} else if (NULL == symbol->datatype) {

   245

		STAGE3_ERROR(4, symbol, symbol, "ANY_REAL data type not valid in this location.");

   246

	}

   247

	return NULL;

   248

}

   249

   250

void *print_datatypes_error_c::visit(integer_c *symbol) {

   251

	if (symbol->candidate_datatypes.size() == 0) {

   252

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

   253

	} else if (NULL == symbol->datatype) {

   254

		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

   255

	}

   256

	return NULL;

   257

}

   258

   259

void *print_datatypes_error_c::visit(neg_real_c *symbol) {

   260

	if (symbol->candidate_datatypes.size() == 0) {

   261

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_REAL data type.");

   262

	} else if (NULL == symbol->datatype) {

   263

		STAGE3_ERROR(4, symbol, symbol, "ANY_REAL data type not valid in this location.");

   264

	}

   265

	return NULL;

   266

}

   267

   268

void *print_datatypes_error_c::visit(neg_integer_c *symbol) {

   269

	if (symbol->candidate_datatypes.size() == 0) {

   270

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

   271

	} else if (NULL == symbol->datatype) {

   272

		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

   273

	}

   274

	return NULL;

   275

}

   276

   277

void *print_datatypes_error_c::visit(binary_integer_c *symbol) {

   278

	if (symbol->candidate_datatypes.size() == 0) {

   279

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

   280

	} else if (NULL == symbol->datatype) {

   281

		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

   282

	}

   283

	return NULL;

   284

}

   285

   286

void *print_datatypes_error_c::visit(octal_integer_c *symbol) {

   287

	if (symbol->candidate_datatypes.size() == 0) {

   288

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

   289

	} else if (NULL == symbol->datatype) {

   290

		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

   291

	}

   292

	return NULL;

   293

}

   294

   295

void *print_datatypes_error_c::visit(hex_integer_c *symbol) {

   296

	if (symbol->candidate_datatypes.size() == 0) {

   297

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for ANY_INT data type.");

   298

	} else if (NULL == symbol->datatype) {

   299

		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

   300

	}

   301

	return NULL;

   302

}

   303

   304

void *print_datatypes_error_c::visit(integer_literal_c *symbol) {

   305

	if (symbol->candidate_datatypes.size() == 0) {

   306

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for %s data type.", elementary_type_c::to_string(symbol->type));

   307

	} else if (NULL == symbol->datatype) {

   308

		STAGE3_ERROR(4, symbol, symbol, "ANY_INT data type not valid in this location.");

   309

	}

   310

	return NULL;

   311

}

   312

   313

void *print_datatypes_error_c::visit(real_literal_c *symbol) {

   314

	if (symbol->candidate_datatypes.size() == 0) {

   315

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for %s data type.", elementary_type_c::to_string(symbol->type));

   316

	} else if (NULL == symbol->datatype) {

   317

		STAGE3_ERROR(4, symbol, symbol, "ANY_REAL data type not valid in this location.");

   318

	}

   319

	return NULL;

   320

}

   321

   322

void *print_datatypes_error_c::visit(bit_string_literal_c *symbol) {

   323

	if (symbol->candidate_datatypes.size() == 0) {

   324

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for %s data type.", elementary_type_c::to_string(symbol->type));

   325

	} else if (NULL == symbol->datatype) {

   326

		STAGE3_ERROR(4, symbol, symbol, "ANY_BIT data type not valid in this location.");

   327

	}

   328

	return NULL;

   329

}

   330

   331

void *print_datatypes_error_c::visit(boolean_literal_c *symbol) {

   332

	if (symbol->candidate_datatypes.size() == 0) {

   333

		STAGE3_ERROR(0, symbol, symbol, "Value is not valid for %s data type.", elementary_type_c::to_string(symbol->type));

   334

	} else if (NULL == symbol->datatype) {

   335

		STAGE3_ERROR(4, symbol, symbol, "ANY_BOOL data type not valid in this location.");

   336

	}

   337

	return NULL;

   338

}

   339

   340

void *print_datatypes_error_c::visit(boolean_true_c *symbol) {

   341

	if (symbol->candidate_datatypes.size() == 0) {

   342

		STAGE3_ERROR(0, symbol, symbol, "Value is not valid for ANY_BOOL data type.");

   343

	} else if (NULL == symbol->datatype) {

   344

		STAGE3_ERROR(4, symbol, symbol, "ANY_BOOL data type not valid in this location.");

   345

	}

   346

	return NULL;

   347

}

   348

   349

void *print_datatypes_error_c::visit(boolean_false_c *symbol) {

   350

	if (symbol->candidate_datatypes.size() == 0) {

   351

		STAGE3_ERROR(0, symbol, symbol, "Value is not valid for ANY_BOOL data type.");

   352

	} else if (NULL == symbol->datatype) {

   353

		STAGE3_ERROR(4, symbol, symbol, "ANY_BOOL data type not valid in this location.");

   354

	}

   355

	return NULL;

   356

}

   357

   358

/*******************************/

   359

/* B.1.2.2   Character Strings */

   360

/*******************************/

   361

void *print_datatypes_error_c::visit(double_byte_character_string_c *symbol) {

   362

	if (symbol->candidate_datatypes.size() == 0) {

   363

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for WSTRING data type.");

   364

	} else if (NULL == symbol->datatype) {

   365

		STAGE3_ERROR(4, symbol, symbol, "WSTRING data type not valid in this location.");

   366

	}

   367

	return NULL;

   368

}

   369

   370

void *print_datatypes_error_c::visit(single_byte_character_string_c *symbol) {

   371

	if (symbol->candidate_datatypes.size() == 0) {

   372

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for STRING data type.");

   373

	} else if (NULL == symbol->datatype) {

   374

		STAGE3_ERROR(4, symbol, symbol, "STRING data type not valid in this location.");

   375

	}

   376

	return NULL;

   377

}

   378

   379

/***************************/

   380

/* B 1.2.3 - Time Literals */

   381

/***************************/

   382

/************************/

   383

/* B 1.2.3.1 - Duration */

   384

/************************/

   385

void *print_datatypes_error_c::visit(duration_c *symbol) {

   386

	if (symbol->candidate_datatypes.size() == 0) {

   387

		STAGE3_ERROR(0, symbol, symbol, "Invalid syntax for TIME data type.");

   388

	} else if (NULL == symbol->datatype) {

   389

		STAGE3_ERROR(4, symbol, symbol, "TIME data type not valid in this location.");

   390

	}

   391

	return NULL;

   392

}

   393

   394

/************************************/

   395

/* B 1.2.3.2 - Time of day and Date */

   396

/************************************/

   397

void *print_datatypes_error_c::visit(time_of_day_c *symbol) {

   398

	if (symbol->candidate_datatypes.size() == 0) {

   399

		STAGE3_ERROR(0, symbol, symbol, "Invalid syntax for TOD data type.");

   400

	} else if (NULL == symbol->datatype) {

   401

		STAGE3_ERROR(4, symbol, symbol, "TOD data type not valid in this location.");

   402

	}

   403

	return NULL;

   404

}

   405

   406

void *print_datatypes_error_c::visit(date_c *symbol) {

   407

	if (symbol->candidate_datatypes.size() == 0) {

   408

		STAGE3_ERROR(0, symbol, symbol, "Invalid syntax for DATE data type.");

   409

	} else if (NULL == symbol->datatype) {

   410

		STAGE3_ERROR(4, symbol, symbol, "DATE data type not valid in this location.");

   411

	}

   412

	return NULL;

   413

}

   414

   415

void *print_datatypes_error_c::visit(date_and_time_c *symbol) {

   416

	if (symbol->candidate_datatypes.size() == 0) {

   417

		STAGE3_ERROR(0, symbol, symbol, "Invalid syntax for DT data type.");

   418

	} else if (NULL == symbol->datatype) {

   419

		STAGE3_ERROR(4, symbol, symbol, "DT data type not valid in this location.");

   420

	}

   421

	return NULL;

   422

}

   423

   424

/**********************/

   425

/* B 1.3 - Data types */

   426

/**********************/

   427

/********************************/

   428

/* B 1.3.3 - Derived data types */

   429

/********************************/

   430

void *print_datatypes_error_c::visit(data_type_declaration_c *symbol) {

   431

	// TODO !!!

   432

	/* for the moment we must return NULL so semantic analysis of remaining code is not interrupted! */

   433

	return NULL;

   434

}

   435

   436

void *print_datatypes_error_c::visit(enumerated_value_c *symbol) {

   437

	if (symbol->candidate_datatypes.size() == 0)

   438

		STAGE3_ERROR(0, symbol, symbol, "Ambiguous enumerate value or Variable not declared in this scope.");

   439

	return NULL;

   440

}

   441

   442

   443

/*********************/

   444

/* B 1.4 - Variables */

   445

/*********************/

   446

void *print_datatypes_error_c::visit(symbolic_variable_c *symbol) {

   447

	if (symbol->candidate_datatypes.size() == 0)

   448

		STAGE3_ERROR(0, symbol, symbol, "Variable not declared in this scope.");

   449

	return NULL;

   450

}

   451

   452

/********************************************/

   453

/* B 1.4.1 - Directly Represented Variables */

   454

/********************************************/

   455

void *print_datatypes_error_c::visit(direct_variable_c *symbol) {

   456

	if (symbol->candidate_datatypes.size() == 0)

   457

		STAGE3_ERROR(0, symbol, symbol, "Numerical value exceeds range for located variable data type.");

   458

	return NULL;

   459

}

   460

   461

/*************************************/

   462

/* B 1.4.2 - Multi-element variables */

   463

/*************************************/

   464

/*  subscripted_variable '[' subscript_list ']' */

   465

// SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   466

void *print_datatypes_error_c::visit(array_variable_c *symbol) {

   467

	if (symbol->candidate_datatypes.size() == 0)

   468

		STAGE3_ERROR(0, symbol, symbol, "Array variable not declared in this scope.");

   469

   470

	/* recursively call the subscript list to print any errors in the expressions used in the subscript...*/

   471

	symbol->subscript_list->accept(*this);

   472

	return NULL;

   473

}

   474

   475

/* subscript_list ',' subscript */

   476

// SYM_LIST(subscript_list_c)

   477

/* NOTE: we inherit from iterator visitor, so we do not need to implement this method... */

   478

#if 0

   479

void *print_datatypes_error_c::visit(subscript_list_c *symbol) {

   480

}

   481

#endif

   482

   483

   484

/*  record_variable '.' field_selector */

   485

/*  WARNING: input and/or output variables of function blocks

   486

 *           may be accessed as fields of a structured variable!

   487

 *           Code handling a structured_variable_c must take

   488

 *           this into account!

   489

 */

   490

// SYM_REF2(structured_variable_c, record_variable, field_selector)

   491

/* NOTE: We do not recursively determine the data types of each field_selector in fill_candidate_datatypes_c,

   492

 * so it does not make sense to recursively visit all the field_selectors to print out error messages. 

   493

 * Maybe in the future, if we find the need to print out more detailed error messages, we might do it that way. For now, we don't!

   494

 */

   495

void *print_datatypes_error_c::visit(structured_variable_c *symbol) {

   496

	if (symbol->candidate_datatypes.size() == 0)

   497

		STAGE3_ERROR(0, symbol, symbol, "Undeclared structured/FB variable.");

   498

	return NULL;

   499

}

   500

   501

/************************************/

   502

/* B 1.5 Program organization units */

   503

/************************************/

   504

/*********************/

   505

/* B 1.5.1 Functions */

   506

/*********************/

   507

void *print_datatypes_error_c::visit(function_declaration_c *symbol) {

   508

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   509

	/* We do not check for data type errors in variable declarations, Skip this for now... */

   510